Here I go under the bus
Put as much rod in a motor as practicle. Practicle meaning, stay out of the water jackets and the oil ring land.
Every one knows a 350 rev's better than a 400 right? look at the rod stroke ratio's
5.5rod divided by 3.78 stroke = 1.48 (stock 400)
5.7rod divided by 3.48 stroke = 1.63 (stock 350)
6.0rod divided by 3.75 stroke = 1.60 (long rod 400)
Piston speed is slowed down with a longer rod, rod angularity is reduced. Piston location is changed in relation to crank angle. The longer rod a motor has the less Dynamic compression. Which means more compression available on pump gas.
Mahle's new 6" rod piston uses thinner and better rings which keeps the pin out of the oil land.